U.S. patent application number 17/125137 was filed with the patent office on 2021-07-22 for low profile ribbon frame for valve repair devices.
The applicant listed for this patent is Boston Scientific Scimed, Inc.. Invention is credited to James M. Anderson, John M. Edgell, Joshua M. Inouye, Graham Krumpelmann.
Application Number | 20210220136 17/125137 |
Document ID | / |
Family ID | 1000005307174 |
Filed Date | 2021-07-22 |
United States Patent
Application |
20210220136 |
Kind Code |
A1 |
Krumpelmann; Graham ; et
al. |
July 22, 2021 |
LOW PROFILE RIBBON FRAME FOR VALVE REPAIR DEVICES
Abstract
A low profile implant, system and method of deployment includes
a frame comprising an elongate body having ends that overlap to
form an annular configuration of the frame. A circumference of the
frame may be modified by varying an extent of the overlap between
the ends of the elongate body. The elongate structure may extend
through a sleeve of a number of respective anchor housings of the
implant along a first axis, and anchors may be deployed through
bores in the anchor housings along a second axis to secure the
anchor housings to tissue. The implant may be deployed about and
anchored to a valve annulus, and the circumference of the frame,
and associated anchored tissue, may be adjusted to reconfigure the
valve annulus.
Inventors: |
Krumpelmann; Graham;
(Stillwater, MN) ; Inouye; Joshua M.; (Maple
Grove, MN) ; Anderson; James M.; (Corcoran, MN)
; Edgell; John M.; (Plymouth, MN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Boston Scientific Scimed, Inc. |
Maple Grove |
MN |
US |
|
|
Family ID: |
1000005307174 |
Appl. No.: |
17/125137 |
Filed: |
December 17, 2020 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
62963786 |
Jan 21, 2020 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61F 2230/0091 20130101;
A61F 2210/0014 20130101; A61F 2220/0016 20130101; A61F 2250/001
20130101; A61L 27/042 20130101; A61F 2/2445 20130101 |
International
Class: |
A61F 2/24 20060101
A61F002/24 |
Claims
1. An implant comprising: a frame comprising an elongate body
having an annular configuration with an adjustable circumference;
an anchor housing comprising a sleeve having a sleeve passage
extending through the anchor housing along a first axis and a bore
extending through the anchor housing along a second axis, different
from the first axis; and an adjustment mechanism configured to
adjust the adjustable circumference of the frame; wherein the
elongate body of the frame is translatably disposed within the
sleeve passage of the anchor housing.
2. The implant of claim 1, including an anchor translatably
disposed within the bore of the anchor housing.
3. The implant of claim 2, further including a retention mechanism
configured to retain the frame at the adjusted circumference by
inhibiting translation of the elongate body through the sleeve of
the anchor housing by securing the elongate body between an
internal wall of the sleeve of the anchor housing and the retention
mechanism.
4. The implant of claim 3, wherein the retention mechanism includes
a cam lock disposed about the anchor and having a locked
configuration wherein a cam arm of the cam lock urges the elongate
body towards a sidewall of the sleeve to inhibit translation of the
elongate body through the sleeve.
5. The implant of claim 4, wherein: the anchor comprises a proximal
shaft disposed along the second axis; the retention mechanism
comprises a ledge extending radially from the proximal shaft
towards the sleeve, and an arm extending distally from the ledge;
and the retention arm is aligned with the sleeve passage and
configured to extend into the sleeve passage when the ledge is
distally translated to urge the elongate body of the sleeve towards
an end wall of the anchor housing to inhibit translation of the
elongate body through the sleeve.
6. The implant of claim 1, wherein the elongate body includes
plurality of grooves disposed at least partially along at least one
surface, and the adjustment mechanism includes a gear having a
plurality of teeth extending into the sleeve of the anchor housing,
and wherein actuation of the gear engages the plurality of teeth of
the gear with the plurality of grooves of the elongate body to
translate the elongate body through the sleeve.
7. The implant of claim 6, wherein the anchor housing is one of a
plurality of anchor housings of the implant, the elongate body
extending through each of the anchor housings of the plurality of
anchor housings, and wherein at least one of the anchor housings
includes the gear.
8. The implant of claim 1, wherein the elongate body comprises a
ribbon frame, and the ribbon frame is comprised of stainless steel,
a shaped memory alloy, a polymer or a combination thereof, the
ribbon frame having a first end and a second end that overlap in
the annular configuration, wherein the adjustable circumference is
based on an extent of overlap between the first end and the second
end.
9. The implant of claim 8, wherein the ribbon frame comprises a
first compressed configuration enabling the frame to be
transluminally advanced to a treatment site and an expanded
configuration having an annulus repair circumference selected to
position the ribbon frame about a valve annulus.
10. The implant of claim 8, wherein the ribbon frame comprises at
least one blunted edge, at least one stress diffusion feature, or
combination thereof.
11. The implant of claim 1, wherein: the anchor housing comprises a
plurality of anchor housings each having an anchor sleeve with a
passage therethrough; the elongate body comprises a plurality of
elongate bodies, each elongate body of the plurality of elongate
bodies extending through a corresponding sleeve passage in a pair
of adjacent anchor housings; and the adjustment mechanism comprises
more than one adjustment mechanism, each of the more than one
adjustment mechanisms associated with a selected one of the
plurality of elongate bodies to adjust spacing between the anchor
housing pair through which the selected one of the plurality of
elongate bodies extends.
12. An implant comprising: a plurality of anchor housings, each
anchor housing having a sleeve with a sleeve passage and a bore
extending therethrough, wherein the sleeve extends through the
anchor housing along a first axis, and the bore extends through the
anchor housing along a second axis, different from the first axis;
a plurality of anchors, each anchor extending through one of the
plurality of anchor housings, each anchor including a sharpened
distal tip; a frame comprising an elongate body extending through
each sleeve of each anchor housing, the elongate body having an
annular configuration configured to position the plurality of
anchor housings supported by the frame about a valve annulus; and
an adjustment mechanism configured to adjust a circumference of the
frame.
13. The implant of claim 12, including a retention mechanism
disposed within at least one anchor housing and configured to
inhibit translation of the elongate body through the plurality of
anchor housings.
14. The implant of claim 13, wherein the elongate body is comprised
of stainless steel, a shaped memory alloy, a polymer, or a
combination thereof, and includes a first end and a second end that
overlap in the annular configuration, wherein the circumference of
the frame is based on an extent of overlap between the first end
and the second end.
15. The implant of claim 12, wherein the elongate body includes
plurality of grooves disposed at least partially along at least one
surface, and the adjustment mechanism is disposed in at least one
anchor housing and includes a gear having a plurality of teeth, and
wherein actuation of the gear engages the plurality of teeth of the
gear with the plurality of grooves of the elongate body to
translate the elongate body through the sleeve.
16. The implant of claim 12, further including a retention
mechanism configured to retain the frame at an adjusted
circumference by inhibiting translation of the elongate body
through at least one sleeve of at least one anchor housing by
securing the elongate body between an internal wall of the at least
one sleeve of the at least one anchor housing and the retention
mechanism.
17. The implant of claim 16, wherein the retention mechanism
includes a cam lock disposed about the anchor and having a locked
configuration wherein a cam arm of the cam lock urges the elongate
body towards a sidewall of the at least one sleeve to inhibit
translation of the elongate body through the at least one
sleeve.
18. The implant of claim 16, wherein at least one anchor associated
with at least one anchor housing comprises a proximal shaft
disposed along the second axis, and the retention mechanism
comprises an arm that extends radially from the proximal shaft
towards a sleeve of the at least one anchor housing, and a stopper,
extending distally from the arm, the stopper aligned with the
sleeve and configured to extend into the sleeve when the arm is
distally translated to urge the elongate body towards an end wall
of the at least one anchor housing to inhibit translation of the
elongate body through the sleeve.
19. A method of valvular repair comprising: advancing a distal end
of a delivery catheter to a valve treatment site, the distal end of
the delivery catheter having an implant disposed therein; releasing
the implant from the distal end of the delivery catheter, wherein
the implant includes a plurality of anchor housings supporting a
plurality of anchors, each anchor housing comprising a sleeve with
a sleeve passage extending therethrough, wherein the implant
includes a frame comprising an elongate body threaded through each
sleeve of the plurality of anchor housings, wherein ends of the
elongate body overlap through at least some of the sleeves of the
plurality of anchor housings; expanding the frame to position the
anchor housings about a valve annulus; adjusting a circumference of
the frame to an annular reconfiguration circumference; driving the
plurality of anchors into tissue of a valve annulus; and securing
the frame within at least one sleeve of at least one anchor housing
to inhibit translation of the elongate body through the at least
one sleeve to retain the annular reconfiguration circumference of
the frame.
20. The method of claim 19, wherein at least one anchor housing
includes a gear comprising a plurality of teeth, and at least a
portion of the elongate body includes a plurality of grooves, and
wherein adjusting the circumference includes actuating the gear to
engage grooves of the elongate body to move the elongate body
through the anchor housing.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims the benefit of priority under
35 U.S.C. .sctn. 119 to U.S. Provisional Patent Application
62/963,786, filed Jan. 21, 2020, which application is incorporated
herein by reference in its entirety for all purposes.
FIELD
[0002] The present disclosure relates generally to the field of
implantable medical devices. In particular, the present disclosure
relates to medical devices, systems, and methods for annuloplasty
and other cardiac treatment techniques.
BACKGROUND
[0003] Mitral insufficiency (MI) (also referred to as mitral
regurgitation or mitral incompetence) is a form of heart disease
where the mitral annulus dilates excessively and the valve leaflets
no longer effectively close, or coapt, during systolic contraction.
Regurgitation of blood occurs during ventricular contraction and
cardiac output may decrease as a result. Surgical and endoluminal
annuloplasty techniques have been introduced that aim to restore a
mitral valve to its native configuration, for example by implanting
an annuloplasty ring around a valve annulus. One problem
encountered by such implants is that their size may cause
unintended contact between the implant and the cardiac wall,
reducing the efficacy of the implant. It is desirable to minimize
the size of an implant to reduce the opportunity for such contact
and it is with these considerations in mind that the improvements
of the present disclosure may be useful.
SUMMARY
[0004] Embodiments of the present disclosure relate to a system,
device and method for reshaping a valve annulus such as a heart
valve annulus. According to one aspect, an implant includes a frame
including an elongate body having an annular configuration with an
adjustable circumference, an anchor housing including a sleeve
extending through the anchor housing along a first axis and a bore
extending through the anchor housing along a second axis different
from the first axis, where the elongate body of the frame is
translatably disposed within the sleeve of the frame. The implant
includes an adjustment mechanism configured to adjust the
adjustable circumference of the frame.
[0005] In various embodiments, the implant may include an anchor
translatably disposed within the bore of the anchor housing. The
implant may further include a retention mechanism configured to
retain the frame at the adjusted circumference by inhibiting
translation of the elongate body through the sleeve of the anchor
housing by securing the elongate body between an internal wall of
the sleeve of the anchor housing and the retention mechanism. In
one embodiment, the retention mechanism includes a cam lock
disposed about the anchor and having a locked configuration where a
cam arm of the cam lock urges the elongate body towards a sidewall
of the sleeve to inhibit translation of the elongate body through
the sleeve. In one embodiment, the anchor includes a proximal shaft
and the retention mechanism includes a ledge that extends radially
from the proximal shaft towards the sleeve and an arm, extending
distally from the ledge, the arm aligned with the sleeve and
configured to extend into the sleeve when the ledge is distally
translated to urge the elongate body towards an end wall of the
sleeve to inhibit translation of the elongate body through the
sleeve.
[0006] In one embodiment, the elongate body includes a plurality of
grooves disposed at least partially along at least one surface, and
the adjustment mechanism includes a gear having a plurality of
teeth extending into the sleeve of the anchor housing, where
actuation of the gear engages the plurality of teeth of the gear
with the plurality of grooves of the elongate body to translate the
elongate body through the sleeve. In one embodiment, the anchor
housing is one of a plurality of anchor housings of the implant,
the elongate body extends through each of the anchor housings of
the plurality of anchor housings, and at least one of the anchor
housings includes the gear. In one embodiment, the elongate body
includes a ribbon frame, and the ribbon frame is comprised of
stainless steel, a shaped memory alloy, a polymer or a combination
thereof, the ribbon frame having a first end and a second end that
overlap in the annular configuration, where the adjustable
circumference is based on an extent of overlap between the first
end and the second end. In one embodiment, the ribbon frame
includes a first compressed configuration enabling the frame to be
transluminally advanced to a treatment site and an expanded
configuration including an annulus repair circumference selected to
position the ribbon frame about a valve annulus. In some
embodiments, the implant further includes an expansion mechanism
configured to expand the ribbon frame to an anchoring circumference
larger than the annulus repair circumference. In some embodiments,
the ribbon frame includes at least one blunted edge, at least one
stress diffusion feature or combination thereof
[0007] According to another aspect, an implant includes a plurality
of anchor housings, each anchor housing including a sleeve and a
bore extending therethrough, where the sleeve extends through the
anchor housing along a first axis, and the bore extends through the
anchor housing along a second axis, different from the first axis.
The implant includes a plurality of anchors, each anchor extending
through one of the plurality of anchor housings, each anchor
including a sharpened distal tip and a frame including an elongate
body extending through each sleeve of each anchor housing, the
elongate body including an annular configuration configured to
position the plurality of anchor housings supported by the frame
about a valve annulus. The implant further includes an adjustment
mechanism configured to adjust a circumference of the frame.
[0008] In various embodiments, the implant includes a retention
mechanism disposed within at least one anchor housing and
configured to inhibit translation of the elongate body through the
plurality of anchor housings. In some embodiments, the elongate
body is comprised of stainless steel, a shaped memory alloy, a
polymer or a combination thereof, and includes a first end and a
second end that overlap in the annular configuration, where the
circumference of the frame is based on an extent of overlap between
the first end and the second end. In one embodiment, the elongate
body includes a plurality of grooves disposed at least partially
along at least one surface, the adjustment mechanism is disposed in
at least one anchor housing and includes a gear having a plurality
of teeth, and actuation of the gear engages the plurality of teeth
of the gear with the plurality of grooves of the elongate body to
translate the elongate body through the sleeve.
[0009] In one embodiment, the implant further includes a retention
mechanism configured to retain the frame at an adjusted
circumference by inhibiting translation of the elongate body
through at least one sleeve of at least one anchor housing by
securing the elongate body between an internal wall of the at least
one sleeve of the at least one anchor housing and the retention
mechanism. The retention mechanism may include a cam lock disposed
about the anchor and having a locked configuration where a cam arm
of the cam lock urges the elongate body towards a sidewall of the
at least one sleeve to inhibit translation of the elongate body
through the at least one sleeve. In one embodiment, at least one
anchor associated with at least one anchor housing includes a
proximal shaft disposed along the second axis, and the retention
mechanism includes a ledge that extends radially from the proximal
shaft towards a sleeve of the at least one anchor housing, and an
arm, extending distally from the ledge, the arm aligned with the
sleeve and configured to extend into the sleeve when the ledge is
distally translated to urge the elongate body towards an end wall
of the at least one anchor housing to inhibit translation of the
elongate body through the sleeve.
[0010] According to another aspect, a method of valvular repair
includes the steps of advancing a distal end of a delivery catheter
to a valve treatment site, the distal end of the delivery catheter
having an implant disposed therein and releasing the implant from
the distal end of the delivery catheter. The implant includes a
plurality of anchor housings, each anchor housing including a
sleeve extending therethrough and a frame including an elongate
body threaded through each sleeve of the plurality of anchor
housings, where ends of the elongate body overlap through at least
some of the sleeves of the plurality of anchor housings. The method
includes the steps of expanding the frame to position the anchor
housings about a valve annulus, driving the anchors into the valve
annulus, adjusting a circumference of the frame to an annular
reconfiguration circumference; and securing the frame within at
least one sleeve of at least one anchor housing to inhibit
translation of the elongate body through the at least one sleeve to
retain the annular reconfiguration circumference of the frame.
[0011] According to one embodiment, at least one anchor housing
includes a gear including a plurality of teeth, and at least a
portion of the elongate body includes a plurality of grooves, and
the step of adjusting the circumference includes the steps of
actuating the gear to engage grooves of the elongate body to move
the elongate body through the anchor housing.
[0012] With such an arrangement, a low-profile valve annulus
implant with increased flexibility and a reduced potential for
inadvertent contact with cardiac tissue is provided.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Non-limiting embodiments of the present disclosure are
described by way of example with reference to the accompanying
figures, which are schematic and not intended to be drawn to scale.
In the figures, each identical or nearly identical illustrated
component is typically represented by a single numeral. For
purposes of clarity, not every component is labeled in every
figure, nor is every component of each embodiment shown where
illustration is not necessary to allow those of ordinary skill in
the art to understand the disclosure. In the figures:
[0014] FIG. 1 is a diagram of one embodiment of an implant
comprising a generally ribbon shaped, annular frame having an
adjustable circumference as disclosed in various embodiments
herein;
[0015] FIG. 2 is a cross-sectional view of an anchor housing
configured to support a frame as disclosed herein;
[0016] FIGS. 3A-3F illustrate various embodiments of elongate
bodies that may be used as a frame of an implant disclosed
herein;
[0017] FIGS. 4A-4D illustrate the implant in various configurations
that may be used as part of a valvular repair method as disclosed
herein;
[0018] FIGS. 5A and 5B are cross-sectional views of an anchor
housing illustrating one embodiment of a frame retention mechanism
as disclosed herein;
[0019] FIG. 5C is an enlarged perspective view of a portion of the
frame retention mechanism of FIGS. 5A and 5B.
[0020] FIGS. 6A and 6B are cross-sectional views of an anchor
housing illustrating one embodiment of a frame retention mechanism
as disclosed herein;
[0021] FIG. 7 is a cross-sectional view of an anchor housing
illustrating one embodiment of a frame adjustment mechanism as
disclosed herein;
[0022] FIG. 8 is a perspective view of one embodiment of an implant
including adjustment mechanisms as disclosed herein;
[0023] FIG. 9 is a cross-sectional views of an anchor housing
illustrating one embodiment of a frame adjustment mechanism as
disclosed herein;
[0024] FIG. 10 is a cross-sectional view of one embodiment of an
implant as disclosed herein; and
[0025] FIGS. 11A-11E illustrate an example of a method for valvular
reconfiguration using an illustrative embodiment of an implant such
as that disclosed herein.
DETAILED DESCRIPTION
[0026] A low profile implant, system and method of deployment, as
disclosed herein in various embodiments, includes a frame
comprising a ribbon shaped elongate body that is generally annular
(e.g. circular, ovoid) in form and configured for custom reshaping
of the heart valve. In one embodiment the elongate body may be
threaded through a plurality of anchor housings, for example for
free movement of the elongate body within sleeves of the anchor
housings. The anchor housings may support anchors that may be used
to anchor the anchor housings and the frame to valvular tissue. In
one embodiment, the frame may be adjusted to increase and/or
decrease a circumference of the frame, for example to expand the
circumference of the frame for anchoring the frame about a valve
annulus and/or for cinching the frame to reduce a circumference of
a valve annulus to which the frame is anchored. In some
embodiments, the frame may be formed of a shaped memory material
that automatically assumes a cinched configuration for annular
reshaping. In such embodiments, adjustment mechanisms may include
expansion mechanisms (such as balloons and the like), to expand a
circumference of the frame for anchoring purposes.
[0027] In some embodiments, adjustment mechanisms for increasing
and/or decreasing a circumference of the frame may be included
within one or more of the anchor housings. For example, some frames
may be formed from an elongate body biased in an annular
configuration and having overlapping ends. Adjustment mechanisms
may be provided that modify the circumference of the frame by
increasing or decreasing an extent of overlap of the ends of the
frame. Such adjustment mechanisms, for example, may include gears
comprising teeth that interact with grooves disposed on a surface
of the frame to translate the elongate body through the sleeves of
the anchor housings to achieve a selected annular reconstruction.
Retention mechanisms may be provided by the anchors and/or anchor
housing to inhibit further translation of the elongate member
through the sleeves of the anchor housings, to secure the implant
in the reconstructed configuration.
[0028] These and other beneficial aspects of an implant and method
of deployment are described in more detail below. Although
embodiments of the present disclosure may be described with
specific reference to mitral valves, the principles disclosed
herein may be readily adapted to facilitate reconstruction of any
valve annulus, for example including a tricuspid valve annulus
and/or may similarly benefit any other dilatation, valve
incompetency, valve leakage, and other similar heart failure
conditions.
[0029] As used herein, the term "distal" refers to the end farthest
away from the medical professional when introducing a medical
device into a patient, while the term "proximal" refers to the end
closest to the medical professional when introducing a medical
device into a patient.
[0030] FIG. 1 illustrates an implant 100 comprising a frame 110
that may be disposed about a heart valve or other cardiac feature.
For purposes of clarity, not all the components of the implant are
numbered. In one embodiment, the frame 110 may extend
circumferentially around a central frame axis extending
proximally-distally through a center point of the frame. The frame
110 may be generally symmetric with respect to the central frame
axis although it need not be symmetric. The frame 110 may be
comprised of a generally ribbon shaped elongate body 112 that is
generally annular in shape, where herein "annular" includes
circular, ovoid, as well as other rounded shapes. The frame 110 may
be configured to change shape, size, and/or configuration. For
example, the frame 110 may assume various shapes, sizes,
configurations etc. during different phases of deployment such as
during pre-delivery, delivery, tissue engagement, and cinching.
[0031] According to one embodiment, the elongate body 112 may have
a length at least about 7 cm and at most about 20 cm (corresponding
to the circumference of the annulus at which the elongate body is
to be implanted, which circumference varies depending on patient
and disease state), a width of at least about 1 mm and at most
about 10 mm and a thickness of at least about 0.02 mm and at most
about 2 mm, although the disclosure is not so limited. It is
appreciated that other embodiments of a frame 110 having an
elongate body 112 with a length sufficient to be disposed about a
treatment location, such as but not limited to a mitral valve,
having a width and thickness selected to provide the torsional
rigidity and structural integrity to retain the valve in a
reconstructed configuration and inhibit anchor pullout in the
presence of chronic palpatory forces of the treatment location may
be substituted herein by one of ordinary skill in the art. It will
further be appreciated that the elongate body 112 may be looped
around the annulus so that at least a portion of the elongate body
112 overlaps another portion, and may even loop around the annulus
two or more complete loops, such that the length of the elongate
body 112 may be a multiple of a circumference of an annulus at
which the elongate body 112 is to be implanted.
[0032] In one embodiment, the elongate body 112 may be formed of a
shaped stainless steel, a metal alloy, a shape memory material
(such as an alloy of nickel titanium or other metals), plastics,
polymers, composites, other suitable materials, or combinations
thereof. The elongate body 112 may be threaded through a plurality
of anchor housings 120, for example through a sleeve 125 of anchor
housing 120, along the circumference of the valve, for example
along a generally horizontal axis generally transverse to the
central axis of the valve. The anchor housing may further support
an anchor 130 having a distal helical portion 136. Providing
cinching forces along a different axial plane than that used to
apply anchoring forces advantageously increases the torsional
rigidity of the frame 110, reducing the potential and impact of
anchor pullout.
[0033] In one embodiment, the elongate body 112 comprises an
overlapping portion 115, wherein a first end 113 of the elongate
body 112 floatingly overlaps a second end 117 of the elongate body
112. A circumference of the frame 110 may be modified by varying an
extent of the overlapping portion 115 of the frame. In one
embodiment, the frame 110 is biased to assume a predetermined
configuration having a selected circumference, such as having a
diameter slightly smaller than the idealized annulus diameter so
that the leaflets coapt, for example in the range of 20 mm. In the
predetermined configuration, the freely floating overlapping ends
of the elongate body 112 may move freely within the anchor housing
sleeves 125, enabling a degree of expansion and contraction of the
frame in the presence of chronic palpatory forces while retaining
valve reconfiguration. Such an arrangement minimizes the strain and
fatigue experienced by the implant due to chronic palpatory forces,
improving implant efficacy.
[0034] FIG. 2 depicts a cross-sectional view of the anchor housing
120 including a bore 140 extending therethrough. The anchor housing
may be formed from metallic materials and/or polymers with
sufficient structural integrity for supporting anchors for driving
into the heart annulus. The material may also be chosen based on
biocompatibility and fatigue resistance. Material(s) could include
stainless steel, Nickel-Titanium, Cobalt-Chromium, Pyrolytic
Carbon, Nitinol, polymer materials (e.g., PEEK), and/or other
suitable materials.
[0035] The bore 140 is configured to support an anchor 130 having a
distal helical portion 136 and proximal shaft 132. The helical
portion 136 includes a distal tip that may be a sharpened point
configured to pierce tissue. The proximal shaft 132 may be solid or
hollow. In various embodiments, the proximal shaft 132 and helical
portion 136 may be comprised of the same or different materials.
The proximal shaft 132 may be cylindrical in shape. In some
embodiments, the shaft 132 may be partly cylindrical, rounded,
segmented, other shapes, or combinations thereof.
[0036] In various embodiments the proximal shaft 132 and/or helical
portion 136 of the anchor 130 may be made of a suitable
biocompatible metal alloy such as stainless steel, cobalt chromium,
platinum iridium, nickel titanium, other suitable materials, or
combinations thereof. Each anchor 130 may be at least about 10
millimeters (mm) and at most about 15 mm in total axial length. In
some embodiments, the anchors may be shorter or longer than 10 mm
to 15 mm in axial length. By "total" axial length it is meant the
axial length of the anchor 130 from the end of the distal
penetrating tip of the helical portion 136 to the opposite,
proximal end of the proximal shaft 132. The helical portion 136 may
be at least about 6 mm and at most about 12 mm in axial length,
e.g., in an axial direction. In some embodiments, the helical
portion 136 of the anchor 130 may be shorter or longer than 6 mm to
about 12 mm in axial length. The proximal shaft 132 and/or other
non-helical portions of the anchor may be at least about 1 mm and
at most about 10 mm, such as at most about 5 mm, in axial length.
In some embodiments, the helical diameter range may be at least
about 0.127 mm (0.050'') and at most about 0.203 mm (0.080''), and
the pitch may be about 0.076 mm (0.030'') and at most about 0.203
mm (0.080''), such that the coil pitch angle is about twenty (20)
degrees (e.g., at least about 15 degrees and at most about 30
degrees).
[0037] In one embodiment, at least a portion of a proximal end of
the helical portion 136 may be wrapped around a distal end of the
proximal shaft 132. In some embodiments, the helical portion 136
may be mechanically attached to the proximal shaft 132, such as by
interference or friction fit, with fasteners, adhesives, bands,
other suitable means, or combinations thereof. In some embodiments,
the helical portion 136 may be integral with the proximal shaft
132, for example formed from the same monolithic piece of
material.
[0038] The proximal shaft 132 is shown to include a coupler 135 at
its proximal end. The coupler 135 may be integral with the proximal
shaft 132 or a separate part attached thereto. The coupler 135 is
configured for mated coupling to a drive coupler of a drive tube
(not shown), that may be actuated to drive the anchor 130 into
tissue, for example through distal rotation of the anchor 130
through the bore 140 of the anchor housing 120. In one embodiment,
the proximal shaft 132 may include one or more flanges 133, which
extend radially from the proximal end of the proximal shaft 132. A
circumferential extent of the flanges 133 may be selected such that
the flanges 133 inhibit further translation of the anchor 130
through the bore 140 of the anchor housing 120.
[0039] In some embodiments, the bore 140 may include grooves
disposed on at least a portion of an internal wall of the bore, or
may otherwise be threaded to engage turns of the anchor 130 as it
is driven through the bore 140 into tissue. In some embodiments, at
least a portion of an internal wall of the bore 140 is unthreaded,
providing a free spin area for the anchor 130, wherein, when distal
translation of the anchor 130 is impeded by engagement of the
flanges 133 of the proximal shaft 132 with the anchor housing 120,
the anchor 130 may continue to spin, pulling together the anchor
housing 120 and tissue to improve implant affixation. In one
embodiment, the anchor housing 120 may include a sleeve 125 through
which the elongate body 112 passes so that the anchor housing 120
is configured to slideably translate along the elongate body 112.
For example, in some embodiments the passage 127 within the sleeve
125 may have a height S.sub.H (FIG. 2) that exceeds the width W
(FIG. 3A) of the elongate body 112, and a width S.sub.W (FIG. 2)
that exceeds the thickness T (FIG. 3A) of the elongate body 112. In
some embodiments, the width S.sub.W of the sleeve passage 127 may
exceed a multiple of the thickness T of the elongate body 112, to
accommodate multiple, overlapping turns of the elongate body
through the sleeve, for example when the elongate body is in a
compressed or cinched state as will be described in more detail
later herein. For example, in some embodiments the sleeve passage
127 may have a height at least about 1 mm and at most about 10 mm,
and a width at least about 0.5 mm and at most about 3 mm.
[0040] FIG. 3A illustrates one embodiment of an elongate body 300
in an unshaped form that may be used to form an annular frame such
as that disclosed herein. The elongate body 300 of FIG. 3A is
generally rectangular in shape, having width W that extends
perpendicularly along the Y axis from its length L. As mentioned
above, the elongate body may be formed of stainless steel, nitinol,
or similar material, and may be bent to an annular (circular,
ovoid) formation having overlapping ends, allowing the elongate
body to function similar to the mainspring of a watch. The frame is
shown in FIG. 3A to have a fairly uniform width W and thickness T
over its length L, although this is not a requirement. It may be
desired to have variable torsional stiffness based on the location
of the variable tissue around the annulus. For example, in some
embodiments the width W or thickness T may vary over the length L,
for example being wider in those portions that thread the anchor
housings, and narrower in between, or vice versa. The thickness T
may vary depending upon where the edges of the frame overlap, for
example being thinner in overlapping sections to facilitate
translation of the multiple portions of elongate body as they
thread through the anchor housing.
[0041] In one embodiment, the elongate body 300 may be cut from a
sheet of stainless steel or nitinol, and, as such, the edges, such
as edge 301, may have a propensity to cut into adjacent tissue.
Accordingly, it may be desired to round out or otherwise blunt the
edges of the elongate body to reduce the potential of trauma to
nearby tissue. For example, in some embodiments the edges, such as
edge 301, may be angled or rounded to reduce the potential for
tissue trauma.
[0042] In other embodiments, such as shown in FIGS. 3B-3D, rather
than, or in addition to, rounding the edges 301 of the elongate
body, the elongate body may be formed such that one or both edges
deflect away from the Y axis to reduce the potential for impact
between the edge(s) and tissue. The degree of deflection is a
matter of design choice, and may be, for example, at least about 5
degrees or less and at most about 180 degrees or more.
[0043] For example, in FIG. 3B, the elongate body may be curved so
that both edges 303, 305 deflect away from the Y axis towards each
other, forming a generally rounded elongate body which minimizes
trauma to surrounding tissue. FIG. 3C illustrates an elongate body
320 wherein edges 307, 309 each deflect away from the Y axis in
opposing directions, forming a generally S-shaped body that reduces
or blunts edge trauma to tissue. FIG. 3D illustrates an elongate
body 330 wherein one of the edges 307 is shown curved away from the
Y axis, for example to protect neighboring tissue.
[0044] The elongate body may further be formed to distribute
stresses to reduce potential for device fracture. For example, as
shown in FIG. 3E, an elongate body 340 may be formed with one or
more stress distribution features, including, for example slots 342
or other mechanisms, such as pores or slits, which act to
distribute localized stresses and strains more effectively
throughout the elongate body 340. In some embodiments, for example
as shown in FIG. 3F, portions of, or the entire, elongate body 350,
may be formed of a multi-coil braid or braids (e.g., a single braid
made of multiple coils, multiple braids each made of single or
multiple coils, multiple braids made of multiple coils in parallel,
etc.) which act naturally to dampen chronic stresses while
providing a flexible, strong, implant solution.
[0045] It is appreciated that the elongate body may take many
forms, and that the disclosed embodiments are meant to be
representative and not exhaustive of alternative embodiments. For
example, in various embodiments, as described later herein, the
elongate body may include additional features, such as grooves,
disposed along at least a portion of the elongate body. The grooves
may interact with gears within the anchor housing to adjust frame
circumference. In some embodiments, the elongate body may further
include features that assist in epithelial ingrowth, such as pores,
surface texture, and the like. In some embodiments, the elongate
body may include a drug-eluting coating to resist infection and/or
aid ingrowth. In addition, it is appreciated that the elongate body
may be constructed of a variety of materials which aid in stress
distribution and may be formed in a variety of manners to reduce or
blunt interaction between sharp surfaces and tissue.
[0046] However, according to one aspect, the various embodiments of
elongate bodies may be constructed to be biased to assume an
annular configuration having an adjustable circumference. The
circumference may be minimized through compression of the frame to
enable the implant to be deployed via a delivery catheter to a
treatment site, and the circumference may be maximized through
expansion of the frame for anchoring the implant about a valve
treatment site.
[0047] For example, FIGS. 4A-4D illustrate various configurations
of one embodiment of a frame comprising an annular elongate body
threaded through a plurality of anchor housings. It should be noted
that although eight anchor housings are illustrated, the disclosure
is not limited to an eight anchor housing implant; rather, implants
having as few as two and as many as 16 or more anchor housings are
considered within the scope of this disclosure.
[0048] FIG. 4A illustrates the implant 100 of FIG. 1 in a
compressed configuration, for example when the implant 100 is
disposed within a distal end of a delivery catheter and delivered
to a treatment site. In the pre-deployed state, the anchors 130
extend proximally from the bore 140 of the anchor housing 120,
wherein the distal helical portions 136 of the anchors 130 are
generally disposed within the bore 140 of the anchor housing 120 to
reduce interference during delivery. Drive tubes (not shown for
purposes of clarity), may be coupled to couplers 135 of the
anchors, for driving the anchors 130 through the bores 140 once the
implant is positioned at a treatment site. As shown in FIG. 4A in
the compressed configuration of the frame 110, the elongate body
112 wraps multiple times over itself through the sleeves 125 of the
anchor housings 120.
[0049] FIG. 4B illustrates the implant 100 once released from the
delivery catheter. As in FIG. 4A, pre-deployment, the anchors 130
generally extend proximally from the anchor housings 120 to reduce
interference during implant placement. In one embodiment, the frame
110 of the implant 100, upon release, assumes a predetermined
configuration having a predetermined circumference, wherein the
predetermined circumference may be commensurate with a
circumference of a healthy valve which the implant 100 is to treat.
For example, in FIG. 4B the predetermined configuration produces an
overlapping portion 115, where floating ends 113, 117 of the
elongate body 112 overlap, spanning five anchor housings 120. In
one embodiment, the circumference may be, for example 20 mm,
although it is appreciated that the circumference may vary
depending upon the particular anatomy to be treated, the age, size,
and/or gender of a patient to be treated, and/or a diseased state
of the anatomy to be treated. Accordingly, the disclosure is not
limited to a particular predetermined biased circumference.
[0050] Referring now to FIG. 4C, because the predetermined
circumference is that of a healthy valve, in some embodiments the
frame 110 may be expanded prior to anchoring the frame 110 to
tissue. As mentioned above, the floating ends 113, 117 of the
elongate body 112 enable expansion and contraction of the frame
110. Expansion of the frame may be achieved in a variety of
manners; for example, in one embodiment, a balloon or other
expandable device (not shown) may be disposed within the delivery
catheter, advanced to the center of the frame 110, and expanded to
concomitantly expand the circumference of the frame 110. FIG. 4C
illustrates a frame 110 that has been so expanded. As shown in FIG.
4C, the extent of the overlapping portion 115 is reduced by
expansion of the frame 110 spanning only three anchor housings 120.
Once the frame 110 has been expanded, the anchors 130 may be driven
through the anchor housings 120 into tissue.
[0051] Once the anchors 130 are driven into tissue, the expansion
mechanism may be released, enabling the frame 110 to return to its
predetermined, cinched configuration as shown in FIG. 4D. In the
cinched configuration, the overlap 115 of the ends 113, 117 of the
elongate body 112 returns to span five anchor housings. As
described above, in one embodiment, one or both ends of the
elongate body may be left to float freely through the sleeves,
enabling expansion and contraction of the frame 110 during chronic
use and reducing stresses upon the implant 100.
[0052] According to one aspect, it is recognized that in some
embodiments it may be advantageous to determine a method to
customize the circumference of the frame to address the particular
needs of a patient and/or diseased tissue state. Accordingly, in
various embodiments mechanisms are provided to adjust and/or retain
an extent of overlap of the ends of the elongate body.
[0053] For example, FIGS. 5A-5C illustrate one mechanism that may
be used to set or secure a circumference of a frame, for example to
minimize expansion and/or contraction of the frame in the presence
of chronic forces by inhibiting translation of the elongate body
through the sleeves of the anchor housings. An anchor housing 520
is shown to include a bore 540 extending therethrough configured to
support an anchor 530 having a proximal shaft 532 and a distal
helical portion 536. An anchor sleeve 525 has a passage 527
extending through the anchor housing 520 at an angle transverse to
(e.g., generally perpendicular to) the anchor bore 540. An elongate
body 512, shown in cross section, extends through the sleeve
passage 527 along an axis generally perpendicular to the axis of
the bore 540. A wall 545 separates the anchor sleeve passage 527
from the bore 540 to minimize interference between the anchor 530
and the elongate body 512.
[0054] In one embodiment, a retention mechanism for inhibiting
translation of the elongate body 512 through the sleeve 525
includes an anchor shaft 532 including a cam lock having one or two
cam arms 550, 552. In an open configuration, the cam arms 550, 552
are disposed about the anchor 530 in a manner that reduces
interference with the anchoring process to allow adjustment of the
elongate body 512. In one embodiment, in an open configuration, the
cam arms lie generally flush against the shaft 532. In some
embodiments, in an open configuration the cam arms may be disposed
(e.g., stowed) within a hollow portion of the proximal shaft 532 or
may wrap around the proximal shaft. Other implementations where the
cam arms are disposed about the proximal shaft in a manner that
does not interfere with driving the anchors into tissue are
considered within the scope of this disclosure.
[0055] In some embodiments, when the frame has been cinched, the
cam lock may be used to retain the elongate body within the anchor
housing, to inhibit further translation of the elongate body
through the anchor housing to secure the cinched circumference. For
example, in FIG. 5B when the frame has been adjusted to a desired
circumference, such as the cinched circumference or an adjusted
circumference, the cam lock may be actuated, for example by
rotating shaft 532 to adjust the position of the cam 550, 552
relative to the elongate body 512 to close the cam. When actuated,
the cam arms 550 extend through openings 547 in the wall 545
separating the bore 540 from the sleeve passage 527, urging the
elongate body 512 towards an internal sidewall 526 of the sleeve
passage 527, inhibiting further translation of the elongate body
512 through the sleeve, such as illustrated in FIG. 5C.
[0056] In various embodiments, a retention mechanism (such as the
cam lock) may be included in a single anchor housing 520, in
multiple anchor housings 520, or in all anchor housings 520 of the
implant.
[0057] FIGS. 6A and 6B illustrate an alternate embodiment of a
retention mechanism that may be provided in one or more anchor
housings 620 of implants disclosed herein. In FIG. 6A, an anchor
housing 620 is shown in cross-section to include a bore 640
configured to support an anchor 630 having a proximal shaft 632 and
a distal helical portion 636. The proximal shaft 632 may include a
coupler 635 configured to matingly engage with a coupler 637 of a
drive shaft 639, where rotation of the drive shaft 639 translates
the anchor 630 through the bore 640.
[0058] The anchor housing may also include a sleeve 625 with a
passage 627 extending therethrough along an axis transverse to
(e.g., generally perpendicular to) the axis of the bore 640, the
sleeve positioned and configured for translatably supporting an
elongate body 612 of an implant frame. In one embodiment, an
opening 655 extends through the proximal surface of the anchor
housing 620 into the sleeve 625.
[0059] A ledge 660 is shown disposed about the proximal shaft 632.
The ledge 660 extends radially outward from the proximal shaft 632.
An arm 662 extends distally from the ledge and is positioned over
the opening 655 of the anchor housing 620. In one embodiment, the
arm 662 is sized to slideably advance into the opening 655 of the
anchor housing. A length L.sub.ARM relates to a width of the
elongate body 612 (FIG. 3A) and a depth/height D.sub.S of the
sleeve 625 and is selected to be sufficient to enable the arm 662
to push the elongate body 612 against a distal interior wall 623 of
the sleeve 625 when the arm 662 is advanced into the opening 655
(e.g., to create interference with the elongate body 112 to induce
a clamping load). In one embodiment, advancement of the ledge 660
over the proximal shaft 632 is enabled by distal translation of a
push tube 650 of the proximal shaft 632 following distal
translation of the anchor 630 through the bore 640.
[0060] For example, FIG. 6B illustrates an anchor housing 620
wherein the push tube 650 has been distally advanced to push the
ledge 660 distally over the proximal shaft 632, thereby moving the
arm 662 into the opening 655. Distal advancement of the ledge 660
and arm 662 causes the arm 662 to trap the elongate body 612
between the arm 662 and the distal interior wall 623 in the sleeve
625, inhibiting translation of the elongate body 612 through the
sleeve 625 to set or secure a frame circumference.
[0061] In addition to anchor housings that include retention
mechanisms, implants such as those disclosed herein may
additionally or alternatively incorporate anchor housings that
enable frame circumference adjustment. FIG. 7 illustrates an anchor
housing 720 including one embodiment of a circumference adjustment
mechanism, for example including a gear 750. In one embodiment, the
gear 750 may be coupled to a shaft 755 having a proximal coupler
757 that interacts with a coupler 759 of a drive shaft 760.
Rotation of the drive shaft 760 rotates the gear 750. In one
embodiment, the elongate body 712 may include grooves disposed on
one or more surfaces, the grooves configured to interact with teeth
752 of the gear 750 for controlled translation of the elongate body
712 through the sleeve passage 727 in the sleeve 725 of the anchor
housing 720 in response to rotation of the gear 750.
[0062] FIG. 8 is a top down view of one embodiment of an implant
700 including a plurality of anchor housings 720 including gear
based adjustment mechanisms such as described with regard to FIG.
7. The implant 700 also includes anchor housings 740 which do not
include adjustment mechanisms, and it is appreciated that in
various embodiments implants may include adjustment mechanisms in
one, multiple, or all anchor housings. In FIG. 8, anchor housings
740 with adjustment mechanisms are disposed along that portion of
the implant having overlapping ends 713, 717, enabling the
adjustment mechanisms of the anchor housings 740 to adjust the
extent of overlap.
[0063] In FIG. 8, the elongate body 712 is shown to include grooves
733 disposed over at least a portion of the elongate body 712,
along a surface of the elongate body that is exposed to the gears
of the housings 720. While FIG. 8 illustrates grooves disposed over
only a portion of the elongate body, it is appreciated that in
various embodiments for various reasons, such as ease of
manufacturing, it may be advantageous to dispose grooves over a
portion, over discrete portions, or over the entire length of the
elongate body, and the disclosure is not limited to any particular
pattern of grooves over the elongate body.
[0064] Thus far the disclosure has described frames that include a
unitary elongate body. However, the disclosure is not so limited,
and in one embodiment it is appreciated that a low profile,
adjustable implant may be provided using multiple, discrete
elongate bodies, which may be effectively tied together to form the
frame using anchor housings and individually adjusted using
adjustment mechanisms such as illustrated in FIGS. 7 and 8.
[0065] For example, FIG. 9 illustrates an anchor housing 920
including one embodiment of a circumference adjustment mechanism,
for example including a gear 950. The anchor housing 920 is similar
in form and function to the anchor housing 720 of FIG. 7, however,
the sleeve 925 of the anchor housing 920 is configured to support
multiple elongate bodies 912 and 913, wherein elongate body 913 may
originate and be internally fixed to the sleeve 925, and elongate
body 912 may translate through a passage 927 in the sleeve 925, by
rotation of the gear 950 by driver 960 and interaction between
grooves on a surface of the elongate body 912 and teeth 952 of the
gear 950.
[0066] For example, FIG. 10 is a top down view of an implant 900,
showing anchor housings 920 in cross-sectional view. The anchor
housings 920 are joined by a plurality of separately formed
elongate bodies, 912a-912f, each elongate body originating at an
anchor housing and translatably advanced and adjusted through an
adjacent anchor housing. At least a portion of each elongate body
has grooves disposed thereon to translationally engage teeth of
gears 950 disposed within the anchor housings 920. With such an
arrangement, gears 950 may be individually controlled to adjust
spacing between anchor housing pairs, enabling full customization
of the frame 900 prior to anchoring of the frame 900 to tissue. It
will be appreciated that the concept of providing the elongate body
in the form of a plurality of elongate bodies, each elongate body
extending through a corresponding sleeve passage in a pair of
adjacent anchor housings, may be applied in conjunction with any of
the adjustment mechanisms disclosed herein or otherwise
contemplated. An adjustment mechanism can be provided for at least
one or more of the anchor housings to adjust spacing between
adjacent anchor housings between which an elongate body
extends.
[0067] FIGS. 11A-11E illustrate exemplary steps that may be used to
deploy an implant such as that disclosed herein in various
embodiments to a treatment site, such as a mitral valve. Although a
transseptal delivery is illustrated, it is appreciated that the
implant may be delivered in a minimally invasive percutaneous
manner, such as transfemorally, transeptally, or transapically. In
addition, the implant may be implanted surgically, in that it
should reduce the duration of the procedure and, more particularly,
the duration that the patient is on bypass. The implant may be used
for mitral valve or tricuspid valve procedures.
[0068] In FIG. 11A a delivery catheter 1120 is deployed across the
septum 1111 into the left atrium 1113 of the heart 1100 above a
mitral valve 1116. The delivery catheter 1120 may comprise a
braided steel core with a radiopaque sheath and a guidewire 1112 to
aid in visualization. The delivery catheter 1120 may carry an
implant 1114 at its distal tip.
[0069] FIG. 11B illustrates the implant 1114 prior to release from
the delivery catheter. In one embodiment, a shaft 1115 may include
a retainer 1125 at its distal end, the retainer arranged to
matingly accept tabs 1127 of the anchor housings 1130 to retain the
implant 1114 in a compressed configuration for delivery. As shown
in FIG. 11B, the elongate body 1142 of the frame 1150 is wrapped
around itself within sleeves 1135 of the anchor housings 1130
during delivery.
[0070] As shown in FIG. 11C, distal advancement of the shaft 1115
during deployment of the implant 1114 releases the tabs 1127 of the
anchor housings 1130 from grooves 1123 of the retainer 1125,
enabling the elongate body 1142 to expand to its biased
circumference as described in FIGS. 4A-4D.
[0071] FIG. 11D illustrates the implant 1114 in an expanded state,
which may be, for example an anchoring configuration. In FIGS. 11D
and 11E, only the left portion 1100-L of the heart is shown, and
the number of anchor housings has been reduced to four for clarity
purposes. In FIG. 11D, the frame 1150 is shown expanded beyond its
biased circumference using a balloon 1155 from delivery catheter
1120, to position the frame 1150 at the desired position around the
mitral valve 1116, for example proximate a mitral valve annulus.
The frame 1150 may then be anchored using drive tubes 1202, 1204,
1206 to drive anchors 1222, 1224, and 1226, respectively, into
annular tissue.
[0072] FIG. 11E illustrates the implant 1114, anchored around the
mitral valve 1116 in a cinched configuration comprising an annular
reconstruction configuration. As shown in FIG. 11E, the cinching
action of the frame 1150 as it returns to its biased configuration
pulls together the leaflets of the mitral valve 1116, restoring
valve function. The remaining implant structure 1114, including
only the frame 1150 and the anchor housings 1130, provides a low
profile implant capable of withstanding chronic palpatory
forces.
[0073] Accordingly, a low profile implant, system and method of
delivery have been shown and described. Although embodiments of the
present disclosure may be described with specific reference to
medical devices and systems (e.g., transluminal devices inserted
through a femoral vein or the like) for selective access to heart
tissue, it should be appreciated that such medical devices and
systems may be used in a variety of medical procedures that require
anchoring to heart tissue. The disclosed medical devices and
systems may also be inserted via different access points and
approaches, e.g., percutaneously, endoscopically, laparoscopically,
or combinations thereof.
[0074] As used herein, the singular forms "a," "an," and "the" are
intended to include the plural forms as well, unless the context
clearly indicates otherwise. The terms "comprises" and/or
"comprising," or "includes" and/or "including" when used herein,
specify the presence of stated features, regions, steps, elements,
and/or components, but do not preclude the presence or addition of
one or more other features, regions, integers, steps, operations,
elements, components, and/or groups thereof.
[0075] As used herein, the conjunction "and" includes each of the
structures, components, features, or the like, which are so
conjoined, unless the context clearly indicates otherwise, and the
conjunction "or" includes one or the others of the structures,
components, features, or the like, which are so conjoined, singly
and in any combination and number, unless the context clearly
indicates otherwise.
[0076] All numeric values are herein assumed to be modified by the
term "about," whether or not explicitly indicated. The term
"about," in the context of numeric values, generally refers to a
range of numbers that one of skill in the art would consider
equivalent to the recited value (i.e., having the same function or
result). In many instances, the term "about" may include numbers
that are rounded to the nearest significant figure. Other uses of
the term "about" (i.e., in a context other than numeric values) may
be assumed to have their ordinary and customary definition(s), as
understood from and consistent with the context of the
specification, unless otherwise specified. The recitation of
numerical ranges by endpoints includes all numbers within that
range, including the endpoints (e.g. 1 to 5 includes 1, 1.5, 2,
2.75, 3, 3.80, 4, and 5).
[0077] It is noted that references in the specification to "an
embodiment," "some embodiments," "other embodiments," etc.,
indicate that the embodiment(s) described may include a particular
feature, structure, or characteristic, but every embodiment may not
necessarily include the particular feature, structure, or
characteristic. Moreover, such phrases are not necessarily
referring to the same embodiment. Further, when a particular
feature, structure, or characteristic is described in connection
with an embodiment, it would be within the knowledge of one skilled
in the art to affect such feature, structure, or characteristic in
connection with other embodiments, whether or not explicitly
described, unless clearly stated to the contrary. That is, the
various individual elements described herein, even if not
explicitly shown in a particular combination, are nevertheless
contemplated as being combinable or arrangeable with each other to
form other additional embodiments or to complement and/or enrich
the described embodiment(s), as would be understood by one of
ordinary skill in the art.
[0078] The devices and/or methods disclosed and claimed herein can
be made and executed without undue experimentation in light of the
present disclosure. While various embodiments of the devices and
methods of this disclosure have been described, it may be apparent
to those of skill in the art that variations can be applied to the
devices and/or methods and in the steps or in the sequence of steps
of the method described herein without departing from the concept,
spirit, and scope of the disclosure. All such similar substitutes
and modifications apparent to those skilled in the art are deemed
to be within the spirit, scope, and concept of the disclosure as
defined by the appended claims.
* * * * *